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TBIS 15194:2019
4.3.12.6.2.2 Single-speed system
With the left-hand crank in the forward position, apply a force, F1, increasing
gradually to 1 500 N vertically downwards to the centre of the left-hand pedal.
Maintain this force for 1 min.
Should the system yield or the drive-sprockets tighten such that the crank rotates
while under load to a position more than 30° below the horizontal, remove the test
force, return the crank to the horizontal position or some appropriate position above
the horizontal to take account of yield or movement and repeat the test.
On completion of the test on the left-hand crank repeat the test with the right-hand
crank in the forward position and with the force applied to the right-hand pedal.
4.3.12.6.2.3 Multi-speed system
a) Conduct the tests described in 4.3.12.6.2.2 with the transmission correctly
adjusted in its highest gear;
b) Conduct the tests generally as described in 4.3.12.6.2.2 with the transmission
correctly adjusted in its lowest gear but, where appropriate, with the maximum
force, F1, adjusted to suit the particular gear ratio, thus:
The maximum force, F1, shall be a function of the lowest gear ratio, Nc/Ns,
Where
F1 is the force applied to the pedal, expressed in newton，N；
Nc is the number of teeth on the smallest chain-wheel (front)；
Ns is the number of teeth on the largest sprocket (rear).
Where the ratio Nc/Ns has a value equal to or greater than one, the force, F1, shall
be 1 500 N, but where the ratio Nc/Ns has a value less than one, the force, F1, shall
be reduced in proportion to the lowest gear ratio thus:
F 1 = 1500 × Nc/Ns.
4.3.12.6.3 Test method for drive-system with belt
The sample in its fully finished condition (with teeth if any) shall be submitted to a
water spray conditioning equivalent to IPX4 specified in EN 60529:1991, 14.2.4,
during 10 min. Application of the loading shall be done within 20 min after
conditioning.
a) If the drive-system is a single-speed system, conduct the tests as described in
4.3.12.6.2.2.
b) If the drive-system is a multi-speed system, conduct the tests as described in
4.3.12.6.2.3.
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